I have been using Ubuntu for the past 2 years and actually been on these forums before. I have contemplated whether or not to actually get into Linux for a profession. I have met some Linux system administrators and they seem to be successful. Not sure if I want to be a system admin or not, but I would like to know where to start if I plan to get a job with Linux. I have Centos installed on my other hard drive which I believe is the distribution to have if you honestly want to learn Linux.
Should I just learn from a book and if so can anyone recommend a book?